Below is the error msg I received from PAYPAL.
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Authorization Failed
This transaction is invalid. Please return to the recipient's website to complete your transaction using their regular checkout flow
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Upon futher review, the errors resides in this line....
[ReturnURL]http://my_store_edited_for_post.com/catalog/express_checkout.php[/ReturnURL]
[CancelURL]checkout_payment.php?payment_error=paypal_ec[/CancelURL] <-- ERROR
[shortMessage] = Transaction refused because of an invalid argument. See additional error messages for details.
[LongMessage] = CancelURL is invalid.
[ErrorCode] = 10472
[severityCode] = Warning
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Question
Where should I set the CANCEL URL???